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AJvYcCXJHAuTQmi73r6YZ9UOHjPLVhuDxjBMf6Y+9m0BjhG5Zf/jisXRAr3Dy4FkbBZHcXgIg3KVJm2G/3hfCwI=@vger.kernel.org X-Gm-Message-State: AOJu0YyxJg4tuC3ItyMCXYvapjKqnL4wrJ8Y39DK2dkSbp3xQdVuwJ/P jIRj9ZsNAV8ZvsPuGkzr99G1zcll9Up7Kvq7AHxk4wBsArFEglxQEGf/dpQpLWJiuWqE800gilH gZvLzdw== X-Received: from pjvp18.prod.google.com ([2002:a17:90a:df92:b0:34a:b869:5ed4]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:3811:b0:34c:4c6d:ad0f with SMTP id 98e67ed59e1d1-35272fd8d8fmr903040a91.37.1768520821030; Thu, 15 Jan 2026 15:47:01 -0800 (PST) Date: Thu, 15 Jan 2026 15:46:59 -0800 In-Reply-To: <2kgs2paktjfb33sdr46zhlernx2xgokh5ac4og45obrvvlm34d@2df2kb2u44cy> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260115172154.709024-1-seanjc@google.com> <2kgs2paktjfb33sdr46zhlernx2xgokh5ac4og45obrvvlm34d@2df2kb2u44cy> Message-ID: Subject: Re: [PATCH v5] KVM: selftests: Test READ=>WRITE dirty logging behavior for shadow MMU From: Sean Christopherson To: Yosry Ahmed Cc: Paolo Bonzini , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="us-ascii" On Thu, Jan 15, 2026, Yosry Ahmed wrote: > On Thu, Jan 15, 2026 at 09:21:54AM -0800, Sean Christopherson wrote: > > +static void l2_guest_code(vm_vaddr_t base) > > { > > - READ_ONCE(*a); > > - WRITE_ONCE(*a, 1); > > - GUEST_SYNC(true); > > - GUEST_SYNC(false); > > + vm_vaddr_t page0 = TEST_GUEST_ADDR(base, 0); > > + vm_vaddr_t page1 = TEST_GUEST_ADDR(base, 1); > > > > - WRITE_ONCE(*b, 1); > > - GUEST_SYNC(true); > > - WRITE_ONCE(*b, 1); > > - GUEST_SYNC(true); > > - GUEST_SYNC(false); > > + READ_ONCE(*(u64 *)page0); > > + GUEST_SYNC(page0 | TEST_SYNC_READ_FAULT); > > + WRITE_ONCE(*(u64 *)page0, 1); > > + GUEST_SYNC(page0 | TEST_SYNC_WRITE_FAULT); > > + READ_ONCE(*(u64 *)page0); > > + GUEST_SYNC(page0 | TEST_SYNC_NO_FAULT); > > + > > + WRITE_ONCE(*(u64 *)page1, 1); > > + GUEST_SYNC(page1 | TEST_SYNC_WRITE_FAULT); > > + WRITE_ONCE(*(u64 *)page1, 1); > > + GUEST_SYNC(page1 | TEST_SYNC_WRITE_FAULT); > > + READ_ONCE(*(u64 *)page1); > > + GUEST_SYNC(page1 | TEST_SYNC_NO_FAULT); > > + GUEST_SYNC(page1 | TEST_SYNC_NO_FAULT); > > Extra GUEST_SYNC()? Yeah, I'm guessing it was a copy+paste goof, I can't think of any value added by a second sync here. I'll drop it when applying. Thanks!